Please keep the "Edit" option in Arc available for captions...even after you've uploaded a SRT file that you've edited offline.
In Arc, if you request captions for an original video you have uploaded to your library, you can download those captions in the form of an SRT file. You can then edit that SRT file in either Microsoft Word or the Wordpad software on your PC. Then, you can re-upload the SRT file to your Arc video. However, what if you find a simple mistake in the captions later on that can be fixed in a matter of a few seconds? When you initially request captions for your video, you have the ability to "Edit" those captions online in the Arc interface (following the steps outlined here: How do I add captions to media in an Arc account?). However, once you have clicked on the "Replace" option to upload your edited SRT file, the "Edit" option no longer exists (shown here):
You cannot edit the captions again in the online environment. You'd either have to keep a copy of the SRT file on your PC or re-download the SRT to make the necessary updates and then re-upload it via the "Replace" option.